The GERO Cell Immortalization and Transfection Facility, or CIT, will be supervised by Dr. MacDougall as project leader. The Service Core is designed to serve the 4 scientific projects of the Research Core, and each project will require tooth specific and stably transfected cell lines. The Service Core will produce immortalized cell lines by gene transfer to several dental cell types in monolayer culture, through use of retroviral oncogene constructs. Stable cell lines will be isolated and gene expression profile and nature of extracellular matrix will be analyzed. These cell lines will serve as a resource for in vitro promoter studies in the Research Core projects. The Service Core will also perform stable cell transfections with various promoter-reporter constructs provided by the individual projects.